llvm-project/polly/lib/CodeGen/BlockGenerators.cpp

719 lines
26 KiB
C++

//===--- BlockGenerators.cpp - Generate code for statements -----*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the BlockGenerator and VectorBlockGenerator classes,
// which generate sequential code and vectorized code for a polyhedral
// statement, respectively.
//
//===----------------------------------------------------------------------===//
#include "polly/ScopInfo.h"
#include "isl/aff.h"
#include "isl/set.h"
#include "polly/CodeGen/BlockGenerators.h"
#include "polly/CodeGen/CodeGeneration.h"
#include "polly/Options.h"
#include "polly/Support/GICHelper.h"
#include "polly/Support/SCEVValidator.h"
#include "polly/Support/ScopHelper.h"
#include "llvm/Analysis/LoopInfo.h"
#include "llvm/Analysis/ScalarEvolution.h"
#include "llvm/Analysis/ScalarEvolutionExpander.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
using namespace llvm;
using namespace polly;
static cl::opt<bool>
Aligned("enable-polly-aligned", cl::desc("Assumed aligned memory accesses."),
cl::Hidden, cl::value_desc("OpenMP code generation enabled if true"),
cl::init(false), cl::ZeroOrMore, cl::cat(PollyCategory));
static cl::opt<bool, true>
SCEVCodegenF("polly-codegen-scev", cl::desc("Use SCEV based code generation."),
cl::Hidden, cl::location(SCEVCodegen), cl::init(false),
cl::ZeroOrMore, cl::cat(PollyCategory));
bool polly::SCEVCodegen;
bool polly::canSynthesize(const Instruction *I, const llvm::LoopInfo *LI,
ScalarEvolution *SE, const Region *R) {
if (SCEVCodegen) {
if (!I || !SE->isSCEVable(I->getType()))
return false;
if (const SCEV *Scev = SE->getSCEV(const_cast<Instruction *>(I)))
if (!isa<SCEVCouldNotCompute>(Scev))
if (!hasScalarDepsInsideRegion(Scev, R))
return true;
return false;
}
Loop *L = LI->getLoopFor(I->getParent());
return L && I == L->getCanonicalInductionVariable() && R->contains(L);
}
// Helper class to generate memory location.
namespace {
class IslGenerator {
public:
IslGenerator(IRBuilder<> &Builder, std::vector<Value *> &IVS)
: Builder(Builder), IVS(IVS) {}
Value *generateIslVal(__isl_take isl_val *Val);
Value *generateIslAff(__isl_take isl_aff *Aff);
Value *generateIslPwAff(__isl_take isl_pw_aff *PwAff);
private:
typedef struct {
Value *Result;
class IslGenerator *Generator;
} IslGenInfo;
IRBuilder<> &Builder;
std::vector<Value *> &IVS;
static int mergeIslAffValues(__isl_take isl_set *Set, __isl_take isl_aff *Aff,
void *User);
};
}
Value *IslGenerator::generateIslVal(__isl_take isl_val *Val) {
Value *IntValue = Builder.getInt(APIntFromVal(Val));
return IntValue;
}
Value *IslGenerator::generateIslAff(__isl_take isl_aff *Aff) {
Value *Result;
Value *ConstValue;
isl_val *Val;
Val = isl_aff_get_constant_val(Aff);
ConstValue = generateIslVal(Val);
Type *Ty = Builder.getInt64Ty();
// FIXME: We should give the constant and coefficients the right type. Here
// we force it into i64.
Result = Builder.CreateSExtOrBitCast(ConstValue, Ty);
unsigned int NbInputDims = isl_aff_dim(Aff, isl_dim_in);
assert((IVS.size() == NbInputDims) &&
"The Dimension of Induction Variables must match the dimension of the "
"affine space.");
for (unsigned int i = 0; i < NbInputDims; ++i) {
Value *CoefficientValue;
Val = isl_aff_get_coefficient_val(Aff, isl_dim_in, i);
if (isl_val_is_zero(Val)) {
isl_val_free(Val);
continue;
}
CoefficientValue = generateIslVal(Val);
CoefficientValue = Builder.CreateIntCast(CoefficientValue, Ty, true);
Value *IV = Builder.CreateIntCast(IVS[i], Ty, true);
Value *PAdd = Builder.CreateMul(CoefficientValue, IV, "p_mul_coeff");
Result = Builder.CreateAdd(Result, PAdd, "p_sum_coeff");
}
isl_aff_free(Aff);
return Result;
}
int IslGenerator::mergeIslAffValues(__isl_take isl_set *Set,
__isl_take isl_aff *Aff, void *User) {
IslGenInfo *GenInfo = (IslGenInfo *)User;
assert((GenInfo->Result == NULL) &&
"Result is already set. Currently only single isl_aff is supported");
assert(isl_set_plain_is_universe(Set) &&
"Code generation failed because the set is not universe");
GenInfo->Result = GenInfo->Generator->generateIslAff(Aff);
isl_set_free(Set);
return 0;
}
Value *IslGenerator::generateIslPwAff(__isl_take isl_pw_aff *PwAff) {
IslGenInfo User;
User.Result = NULL;
User.Generator = this;
isl_pw_aff_foreach_piece(PwAff, mergeIslAffValues, &User);
assert(User.Result && "Code generation for isl_pw_aff failed");
isl_pw_aff_free(PwAff);
return User.Result;
}
BlockGenerator::BlockGenerator(IRBuilder<> &B, ScopStmt &Stmt, Pass *P)
: Builder(B), Statement(Stmt), P(P), SE(P->getAnalysis<ScalarEvolution>()) {
}
Value *BlockGenerator::lookupAvailableValue(const Value *Old, ValueMapT &BBMap,
ValueMapT &GlobalMap) const {
// We assume constants never change.
// This avoids map lookups for many calls to this function.
if (isa<Constant>(Old))
return const_cast<Value *>(Old);
if (Value *New = GlobalMap.lookup(Old)) {
if (Old->getType()->getScalarSizeInBits() <
New->getType()->getScalarSizeInBits())
New = Builder.CreateTruncOrBitCast(New, Old->getType());
return New;
}
// Or it is probably a scop-constant value defined as global, function
// parameter or an instruction not within the scop.
if (isa<GlobalValue>(Old) || isa<Argument>(Old))
return const_cast<Value *>(Old);
if (const Instruction *Inst = dyn_cast<Instruction>(Old))
if (!Statement.getParent()->getRegion().contains(Inst->getParent()))
return const_cast<Value *>(Old);
if (Value *New = BBMap.lookup(Old))
return New;
return NULL;
}
Value *BlockGenerator::getNewValue(const Value *Old, ValueMapT &BBMap,
ValueMapT &GlobalMap, LoopToScevMapT &LTS,
Loop *L) {
if (Value *New = lookupAvailableValue(Old, BBMap, GlobalMap))
return New;
if (SCEVCodegen && SE.isSCEVable(Old->getType()))
if (const SCEV *Scev = SE.getSCEVAtScope(const_cast<Value *>(Old), L)) {
if (!isa<SCEVCouldNotCompute>(Scev)) {
const SCEV *NewScev = apply(Scev, LTS, SE);
ValueToValueMap VTV;
VTV.insert(BBMap.begin(), BBMap.end());
VTV.insert(GlobalMap.begin(), GlobalMap.end());
NewScev = SCEVParameterRewriter::rewrite(NewScev, SE, VTV);
SCEVExpander Expander(SE, "polly");
Value *Expanded = Expander.expandCodeFor(NewScev, Old->getType(),
Builder.GetInsertPoint());
BBMap[Old] = Expanded;
return Expanded;
}
}
// Now the scalar dependence is neither available nor SCEVCodegenable, this
// should never happen in the current code generator.
llvm_unreachable("Unexpected scalar dependence in region!");
return NULL;
}
void BlockGenerator::copyInstScalar(const Instruction *Inst, ValueMapT &BBMap,
ValueMapT &GlobalMap, LoopToScevMapT &LTS) {
Instruction *NewInst = Inst->clone();
// Replace old operands with the new ones.
for (Instruction::const_op_iterator OI = Inst->op_begin(),
OE = Inst->op_end();
OI != OE; ++OI) {
Value *OldOperand = *OI;
Value *NewOperand =
getNewValue(OldOperand, BBMap, GlobalMap, LTS, getLoopForInst(Inst));
if (!NewOperand) {
assert(!isa<StoreInst>(NewInst) &&
"Store instructions are always needed!");
delete NewInst;
return;
}
NewInst->replaceUsesOfWith(OldOperand, NewOperand);
}
Builder.Insert(NewInst);
BBMap[Inst] = NewInst;
if (!NewInst->getType()->isVoidTy())
NewInst->setName("p_" + Inst->getName());
}
std::vector<Value *> BlockGenerator::getMemoryAccessIndex(
__isl_keep isl_map *AccessRelation, Value *BaseAddress, ValueMapT &BBMap,
ValueMapT &GlobalMap, LoopToScevMapT &LTS, Loop *L) {
assert((isl_map_dim(AccessRelation, isl_dim_out) == 1) &&
"Only single dimensional access functions supported");
std::vector<Value *> IVS;
for (unsigned i = 0; i < Statement.getNumIterators(); ++i) {
const Value *OriginalIV = Statement.getInductionVariableForDimension(i);
Value *NewIV = getNewValue(OriginalIV, BBMap, GlobalMap, LTS, L);
IVS.push_back(NewIV);
}
isl_pw_aff *PwAff = isl_map_dim_max(isl_map_copy(AccessRelation), 0);
IslGenerator IslGen(Builder, IVS);
Value *OffsetValue = IslGen.generateIslPwAff(PwAff);
Type *Ty = Builder.getInt64Ty();
OffsetValue = Builder.CreateIntCast(OffsetValue, Ty, true);
std::vector<Value *> IndexArray;
Value *NullValue = Constant::getNullValue(Ty);
IndexArray.push_back(NullValue);
IndexArray.push_back(OffsetValue);
return IndexArray;
}
Value *BlockGenerator::getNewAccessOperand(
__isl_keep isl_map *NewAccessRelation, Value *BaseAddress, ValueMapT &BBMap,
ValueMapT &GlobalMap, LoopToScevMapT &LTS, Loop *L) {
std::vector<Value *> IndexArray = getMemoryAccessIndex(
NewAccessRelation, BaseAddress, BBMap, GlobalMap, LTS, L);
Value *NewOperand =
Builder.CreateGEP(BaseAddress, IndexArray, "p_newarrayidx_");
return NewOperand;
}
Value *BlockGenerator::generateLocationAccessed(const Instruction *Inst,
const Value *Pointer,
ValueMapT &BBMap,
ValueMapT &GlobalMap,
LoopToScevMapT &LTS) {
const MemoryAccess &Access = Statement.getAccessFor(Inst);
isl_map *CurrentAccessRelation = Access.getAccessRelation();
isl_map *NewAccessRelation = Access.getNewAccessRelation();
assert(isl_map_has_equal_space(CurrentAccessRelation, NewAccessRelation) &&
"Current and new access function use different spaces");
Value *NewPointer;
if (!NewAccessRelation) {
NewPointer =
getNewValue(Pointer, BBMap, GlobalMap, LTS, getLoopForInst(Inst));
} else {
Value *BaseAddress = const_cast<Value *>(Access.getBaseAddr());
NewPointer = getNewAccessOperand(NewAccessRelation, BaseAddress, BBMap,
GlobalMap, LTS, getLoopForInst(Inst));
}
isl_map_free(CurrentAccessRelation);
isl_map_free(NewAccessRelation);
return NewPointer;
}
Loop *BlockGenerator::getLoopForInst(const llvm::Instruction *Inst) {
return P->getAnalysis<LoopInfo>().getLoopFor(Inst->getParent());
}
Value *BlockGenerator::generateScalarLoad(const LoadInst *Load,
ValueMapT &BBMap,
ValueMapT &GlobalMap,
LoopToScevMapT &LTS) {
const Value *Pointer = Load->getPointerOperand();
const Instruction *Inst = dyn_cast<Instruction>(Load);
Value *NewPointer =
generateLocationAccessed(Inst, Pointer, BBMap, GlobalMap, LTS);
Value *ScalarLoad =
Builder.CreateLoad(NewPointer, Load->getName() + "_p_scalar_");
return ScalarLoad;
}
Value *BlockGenerator::generateScalarStore(const StoreInst *Store,
ValueMapT &BBMap,
ValueMapT &GlobalMap,
LoopToScevMapT &LTS) {
const Value *Pointer = Store->getPointerOperand();
Value *NewPointer =
generateLocationAccessed(Store, Pointer, BBMap, GlobalMap, LTS);
Value *ValueOperand = getNewValue(Store->getValueOperand(), BBMap, GlobalMap,
LTS, getLoopForInst(Store));
return Builder.CreateStore(ValueOperand, NewPointer);
}
void BlockGenerator::copyInstruction(const Instruction *Inst, ValueMapT &BBMap,
ValueMapT &GlobalMap,
LoopToScevMapT &LTS) {
// Terminator instructions control the control flow. They are explicitly
// expressed in the clast and do not need to be copied.
if (Inst->isTerminator())
return;
if (canSynthesize(Inst, &P->getAnalysis<LoopInfo>(), &SE,
&Statement.getParent()->getRegion()))
return;
if (const LoadInst *Load = dyn_cast<LoadInst>(Inst)) {
Value *NewLoad = generateScalarLoad(Load, BBMap, GlobalMap, LTS);
// Compute NewLoad before its insertion in BBMap to make the insertion
// deterministic.
BBMap[Load] = NewLoad;
return;
}
if (const StoreInst *Store = dyn_cast<StoreInst>(Inst)) {
Value *NewStore = generateScalarStore(Store, BBMap, GlobalMap, LTS);
// Compute NewStore before its insertion in BBMap to make the insertion
// deterministic.
BBMap[Store] = NewStore;
return;
}
copyInstScalar(Inst, BBMap, GlobalMap, LTS);
}
void BlockGenerator::copyBB(ValueMapT &GlobalMap, LoopToScevMapT &LTS) {
BasicBlock *BB = Statement.getBasicBlock();
BasicBlock *CopyBB =
SplitBlock(Builder.GetInsertBlock(), Builder.GetInsertPoint(), P);
CopyBB->setName("polly.stmt." + BB->getName());
Builder.SetInsertPoint(CopyBB->begin());
ValueMapT BBMap;
for (BasicBlock::const_iterator II = BB->begin(), IE = BB->end(); II != IE;
++II)
copyInstruction(II, BBMap, GlobalMap, LTS);
}
VectorBlockGenerator::VectorBlockGenerator(IRBuilder<> &B,
VectorValueMapT &GlobalMaps,
std::vector<LoopToScevMapT> &VLTS,
ScopStmt &Stmt,
__isl_keep isl_map *Schedule,
Pass *P)
: BlockGenerator(B, Stmt, P), GlobalMaps(GlobalMaps), VLTS(VLTS),
Schedule(Schedule) {
assert(GlobalMaps.size() > 1 && "Only one vector lane found");
assert(Schedule && "No statement domain provided");
}
Value *VectorBlockGenerator::getVectorValue(const Value *Old,
ValueMapT &VectorMap,
VectorValueMapT &ScalarMaps,
Loop *L) {
if (Value *NewValue = VectorMap.lookup(Old))
return NewValue;
int Width = getVectorWidth();
Value *Vector = UndefValue::get(VectorType::get(Old->getType(), Width));
for (int Lane = 0; Lane < Width; Lane++)
Vector = Builder.CreateInsertElement(
Vector,
getNewValue(Old, ScalarMaps[Lane], GlobalMaps[Lane], VLTS[Lane], L),
Builder.getInt32(Lane));
VectorMap[Old] = Vector;
return Vector;
}
Type *VectorBlockGenerator::getVectorPtrTy(const Value *Val, int Width) {
PointerType *PointerTy = dyn_cast<PointerType>(Val->getType());
assert(PointerTy && "PointerType expected");
Type *ScalarType = PointerTy->getElementType();
VectorType *VectorType = VectorType::get(ScalarType, Width);
return PointerType::getUnqual(VectorType);
}
Value *VectorBlockGenerator::generateStrideOneLoad(const LoadInst *Load,
ValueMapT &BBMap) {
const Value *Pointer = Load->getPointerOperand();
Type *VectorPtrType = getVectorPtrTy(Pointer, getVectorWidth());
Value *NewPointer =
getNewValue(Pointer, BBMap, GlobalMaps[0], VLTS[0], getLoopForInst(Load));
Value *VectorPtr =
Builder.CreateBitCast(NewPointer, VectorPtrType, "vector_ptr");
LoadInst *VecLoad =
Builder.CreateLoad(VectorPtr, Load->getName() + "_p_vec_full");
if (!Aligned)
VecLoad->setAlignment(8);
return VecLoad;
}
Value *VectorBlockGenerator::generateStrideZeroLoad(const LoadInst *Load,
ValueMapT &BBMap) {
const Value *Pointer = Load->getPointerOperand();
Type *VectorPtrType = getVectorPtrTy(Pointer, 1);
Value *NewPointer =
getNewValue(Pointer, BBMap, GlobalMaps[0], VLTS[0], getLoopForInst(Load));
Value *VectorPtr = Builder.CreateBitCast(NewPointer, VectorPtrType,
Load->getName() + "_p_vec_p");
LoadInst *ScalarLoad =
Builder.CreateLoad(VectorPtr, Load->getName() + "_p_splat_one");
if (!Aligned)
ScalarLoad->setAlignment(8);
Constant *SplatVector = Constant::getNullValue(
VectorType::get(Builder.getInt32Ty(), getVectorWidth()));
Value *VectorLoad = Builder.CreateShuffleVector(
ScalarLoad, ScalarLoad, SplatVector, Load->getName() + "_p_splat");
return VectorLoad;
}
Value *
VectorBlockGenerator::generateUnknownStrideLoad(const LoadInst *Load,
VectorValueMapT &ScalarMaps) {
int VectorWidth = getVectorWidth();
const Value *Pointer = Load->getPointerOperand();
VectorType *VectorType = VectorType::get(
dyn_cast<PointerType>(Pointer->getType())->getElementType(), VectorWidth);
Value *Vector = UndefValue::get(VectorType);
for (int i = 0; i < VectorWidth; i++) {
Value *NewPointer = getNewValue(Pointer, ScalarMaps[i], GlobalMaps[i],
VLTS[i], getLoopForInst(Load));
Value *ScalarLoad =
Builder.CreateLoad(NewPointer, Load->getName() + "_p_scalar_");
Vector = Builder.CreateInsertElement(
Vector, ScalarLoad, Builder.getInt32(i), Load->getName() + "_p_vec_");
}
return Vector;
}
void VectorBlockGenerator::generateLoad(const LoadInst *Load,
ValueMapT &VectorMap,
VectorValueMapT &ScalarMaps) {
if (PollyVectorizerChoice >= VECTORIZER_FIRST_NEED_GROUPED_UNROLL ||
!VectorType::isValidElementType(Load->getType())) {
for (int i = 0; i < getVectorWidth(); i++)
ScalarMaps[i][Load] =
generateScalarLoad(Load, ScalarMaps[i], GlobalMaps[i], VLTS[i]);
return;
}
const MemoryAccess &Access = Statement.getAccessFor(Load);
Value *NewLoad;
if (Access.isStrideZero(isl_map_copy(Schedule)))
NewLoad = generateStrideZeroLoad(Load, ScalarMaps[0]);
else if (Access.isStrideOne(isl_map_copy(Schedule)))
NewLoad = generateStrideOneLoad(Load, ScalarMaps[0]);
else
NewLoad = generateUnknownStrideLoad(Load, ScalarMaps);
VectorMap[Load] = NewLoad;
}
void VectorBlockGenerator::copyUnaryInst(const UnaryInstruction *Inst,
ValueMapT &VectorMap,
VectorValueMapT &ScalarMaps) {
int VectorWidth = getVectorWidth();
Value *NewOperand = getVectorValue(Inst->getOperand(0), VectorMap, ScalarMaps,
getLoopForInst(Inst));
assert(isa<CastInst>(Inst) && "Can not generate vector code for instruction");
const CastInst *Cast = dyn_cast<CastInst>(Inst);
VectorType *DestType = VectorType::get(Inst->getType(), VectorWidth);
VectorMap[Inst] = Builder.CreateCast(Cast->getOpcode(), NewOperand, DestType);
}
void VectorBlockGenerator::copyBinaryInst(const BinaryOperator *Inst,
ValueMapT &VectorMap,
VectorValueMapT &ScalarMaps) {
Loop *L = getLoopForInst(Inst);
Value *OpZero = Inst->getOperand(0);
Value *OpOne = Inst->getOperand(1);
Value *NewOpZero, *NewOpOne;
NewOpZero = getVectorValue(OpZero, VectorMap, ScalarMaps, L);
NewOpOne = getVectorValue(OpOne, VectorMap, ScalarMaps, L);
Value *NewInst = Builder.CreateBinOp(Inst->getOpcode(), NewOpZero, NewOpOne,
Inst->getName() + "p_vec");
VectorMap[Inst] = NewInst;
}
void VectorBlockGenerator::copyStore(const StoreInst *Store,
ValueMapT &VectorMap,
VectorValueMapT &ScalarMaps) {
int VectorWidth = getVectorWidth();
const MemoryAccess &Access = Statement.getAccessFor(Store);
const Value *Pointer = Store->getPointerOperand();
Value *Vector = getVectorValue(Store->getValueOperand(), VectorMap,
ScalarMaps, getLoopForInst(Store));
if (Access.isStrideOne(isl_map_copy(Schedule))) {
Type *VectorPtrType = getVectorPtrTy(Pointer, VectorWidth);
Value *NewPointer = getNewValue(Pointer, ScalarMaps[0], GlobalMaps[0],
VLTS[0], getLoopForInst(Store));
Value *VectorPtr =
Builder.CreateBitCast(NewPointer, VectorPtrType, "vector_ptr");
StoreInst *Store = Builder.CreateStore(Vector, VectorPtr);
if (!Aligned)
Store->setAlignment(8);
} else {
for (unsigned i = 0; i < ScalarMaps.size(); i++) {
Value *Scalar = Builder.CreateExtractElement(Vector, Builder.getInt32(i));
Value *NewPointer = getNewValue(Pointer, ScalarMaps[i], GlobalMaps[i],
VLTS[i], getLoopForInst(Store));
Builder.CreateStore(Scalar, NewPointer);
}
}
}
bool VectorBlockGenerator::hasVectorOperands(const Instruction *Inst,
ValueMapT &VectorMap) {
for (Instruction::const_op_iterator OI = Inst->op_begin(),
OE = Inst->op_end();
OI != OE; ++OI)
if (VectorMap.count(*OI))
return true;
return false;
}
bool VectorBlockGenerator::extractScalarValues(const Instruction *Inst,
ValueMapT &VectorMap,
VectorValueMapT &ScalarMaps) {
bool HasVectorOperand = false;
int VectorWidth = getVectorWidth();
for (Instruction::const_op_iterator OI = Inst->op_begin(),
OE = Inst->op_end();
OI != OE; ++OI) {
ValueMapT::iterator VecOp = VectorMap.find(*OI);
if (VecOp == VectorMap.end())
continue;
HasVectorOperand = true;
Value *NewVector = VecOp->second;
for (int i = 0; i < VectorWidth; ++i) {
ValueMapT &SM = ScalarMaps[i];
// If there is one scalar extracted, all scalar elements should have
// already been extracted by the code here. So no need to check for the
// existance of all of them.
if (SM.count(*OI))
break;
SM[*OI] = Builder.CreateExtractElement(NewVector, Builder.getInt32(i));
}
}
return HasVectorOperand;
}
void VectorBlockGenerator::copyInstScalarized(const Instruction *Inst,
ValueMapT &VectorMap,
VectorValueMapT &ScalarMaps) {
bool HasVectorOperand;
int VectorWidth = getVectorWidth();
HasVectorOperand = extractScalarValues(Inst, VectorMap, ScalarMaps);
for (int VectorLane = 0; VectorLane < getVectorWidth(); VectorLane++)
copyInstScalar(Inst, ScalarMaps[VectorLane], GlobalMaps[VectorLane],
VLTS[VectorLane]);
if (!VectorType::isValidElementType(Inst->getType()) || !HasVectorOperand)
return;
// Make the result available as vector value.
VectorType *VectorType = VectorType::get(Inst->getType(), VectorWidth);
Value *Vector = UndefValue::get(VectorType);
for (int i = 0; i < VectorWidth; i++)
Vector = Builder.CreateInsertElement(Vector, ScalarMaps[i][Inst],
Builder.getInt32(i));
VectorMap[Inst] = Vector;
}
int VectorBlockGenerator::getVectorWidth() { return GlobalMaps.size(); }
void VectorBlockGenerator::copyInstruction(const Instruction *Inst,
ValueMapT &VectorMap,
VectorValueMapT &ScalarMaps) {
// Terminator instructions control the control flow. They are explicitly
// expressed in the clast and do not need to be copied.
if (Inst->isTerminator())
return;
if (canSynthesize(Inst, &P->getAnalysis<LoopInfo>(), &SE,
&Statement.getParent()->getRegion()))
return;
if (const LoadInst *Load = dyn_cast<LoadInst>(Inst)) {
generateLoad(Load, VectorMap, ScalarMaps);
return;
}
if (hasVectorOperands(Inst, VectorMap)) {
if (const StoreInst *Store = dyn_cast<StoreInst>(Inst)) {
copyStore(Store, VectorMap, ScalarMaps);
return;
}
if (const UnaryInstruction *Unary = dyn_cast<UnaryInstruction>(Inst)) {
copyUnaryInst(Unary, VectorMap, ScalarMaps);
return;
}
if (const BinaryOperator *Binary = dyn_cast<BinaryOperator>(Inst)) {
copyBinaryInst(Binary, VectorMap, ScalarMaps);
return;
}
// Falltrough: We generate scalar instructions, if we don't know how to
// generate vector code.
}
copyInstScalarized(Inst, VectorMap, ScalarMaps);
}
void VectorBlockGenerator::copyBB() {
BasicBlock *BB = Statement.getBasicBlock();
BasicBlock *CopyBB =
SplitBlock(Builder.GetInsertBlock(), Builder.GetInsertPoint(), P);
CopyBB->setName("polly.stmt." + BB->getName());
Builder.SetInsertPoint(CopyBB->begin());
// Create two maps that store the mapping from the original instructions of
// the old basic block to their copies in the new basic block. Those maps
// are basic block local.
//
// As vector code generation is supported there is one map for scalar values
// and one for vector values.
//
// In case we just do scalar code generation, the vectorMap is not used and
// the scalarMap has just one dimension, which contains the mapping.
//
// In case vector code generation is done, an instruction may either appear
// in the vector map once (as it is calculating >vectorwidth< values at a
// time. Or (if the values are calculated using scalar operations), it
// appears once in every dimension of the scalarMap.
VectorValueMapT ScalarBlockMap(getVectorWidth());
ValueMapT VectorBlockMap;
for (BasicBlock::const_iterator II = BB->begin(), IE = BB->end(); II != IE;
++II)
copyInstruction(II, VectorBlockMap, ScalarBlockMap);
}